Evaluasi dan Desain Peningkatan Kapasitas Instalasi Pengolahan Air Minum di PT. Krakatau Tirta Industri

Abstract

PT. Krakatau Tirta Industri (PT KTI) has a rule as supplier of Cilegon Municipality’s water needs. Considering the demand for water supply continues to grow, PT. KTI intends to increase its capacity up to 2500 liters/sec. This study aims to evaluate current condition of water treatment plant of PT. KTI, and to review the increasing of installation capacity by process and design aspects. The study is conducted in two stages, namely collecting primary and secondary data and analyzing process and design calculations. Water treatment plant at PT. KTI are bar screen, sand trap, coagulation, flocculation, sedimentation, filtration, and disinfection. Bar screen unit was designed with 40 pieces bar and width of 6 mm. Sand trap unit has minimum height of 4.30 m. Three pumps must have an efficiency of 90%. If the efficiency doesn’t reach that value, then the addition of at least one pump unit is needed. Coagulation unit design is carried out by hydraulic jump and mechanical mixing. Flocculation unit design is done by changing the impeller rotation to 32 rpm. On sedimentation units, plate settlers as much as 891 pieces is designed with inter-plate distance of 0.05 m and height of 1 m. Conclusions of this study are almost all units have parameters that don’t meet the design criteria, and design takes on the unit bar screen, and accelator.